Heart valve regurgitation, or leakage from the outflow to the inflow side of a heart valve, is a condition that occurs when a heart valve fails to close properly. Heart valve regurgitation decreases the efficiency of the heart, reduces blood circulation and adds stress to the heart. In early stages, heart valve regurgitation leaves a person fatigued and short of breath. If left unchecked, the problem can lead to congestive heart failure, arrythmias or death.
Regurgitation through the aortic valve, sometimes referred to as aortic insufficiency, is a serious problem that affects the health of millions of adults. The aortic valve is positioned on the left side of the heart between the left ventricle and the aorta. A healthy aortic valve opens to allow blood to flow from the left ventricle into the aorta during ventricular systole and then closes to prevent blood from flowing backward from the aorta into the left ventricle during ventricular diastole. However, over time, changes in the geometric configurations of the aortic annulus, or other causes such as calcification, infection and injury, may affect the functionality of the aortic valve. As a result, the aortic valve may not close completely during ventricular diastole, thereby leading to regurgitation.
Aortic insufficiency is typically treated by replacing the defective native valve with a prosthetic valve during open heart surgery. However, open-heart surgery is highly invasive and is therefore not an option for many high risk patients. Accordingly, in recent years, less invasive methods, such as percutaneous valve replacement, have been developed for replacing aortic valves. In an example, a prosthesis including a stent and a valve is crimped into a small profile and then delivered into the heart via a percutaneous route. Once located at the treatment site, the prosthesis is expanded to replace the function of the native aortic valve. Although percutaneous valve replacement has shown great promise, there are still challenges with respect to delivery techniques, perivalvular leakage and durability of the valve. Furthermore, when possible, it may be desirable to repair, rather than replace, the native valve.